Some article handling systems include an article flow path having multiple conveyors that run at different speeds from one another. A conventional interface between such conveyors may be a direct transfer from one conveyor to another with minimal spacing in between or an indirect transfer across a non-moving element such as a “dead plate,” or a set of idler rollers or the like.
In certain applications, maintaining the integrity of objects conveyed across such interface is of increased importance. In some such systems, groups of objects (i.e., a number of bottles or cans) are loosely encircled in a sheet of shrinkable plastic while traversing one conveyor, and are then passed to a second conveyor for shrinking of the sheet (for example in a heated shrink tunnel). The objects when loosely encircled by the sheet may ride on a blank or tray, or they made simply be grouped and ride directly on the conveyor. In other systems, a single object is individually wrapped (i.e., a box). Some systems alternate between single objects and groups of objects. Regardless of whether a single object or grouping of objects is being wrapped, such items may all be called an “article” herein.
In all such systems above, a portion of the sheet is typically located beneath the article be wrapped (between the article and the conveyor on which it rides). Often leading and trailing edges of the sheet overlap beneath the article and are held in place via gravity of the article on the conveyor.
The sheets are placed about the article in a predetermined fashion so that upon heating in the shrink tunnel a desired package is achieved by the shrunken film. If the positioning (including any of such overlap that might be present) is disrupted during direct transfer between conveyors of differing speeds and/or indirect transfer across a dead plate, the package formed may be not as desired.
Accordingly, improved devices and methods of transferring articles from conveyor to conveyor, particularly conveyors that may be run at differing speeds, whether addressing one or more of the above issues and/or other issues, would be welcome.